Three Irish school girls hope infecting cereal crops with bacteria might help boost plant yields. The teenagers have spent the past three years researching a bacteria known as rhizobium. Their research helped them win this year's Google Science Fair, an international competition for young scientists. Brett Worthington spoke with the teens, Ciara Judge, Sophie Healy-Thow and Emer Hickey, who say the bacteria can help boost barley crop yields by almost 75 per cent. Read more